
527Iron Production
General rules of thumb can be given for relationship
between air-preheat and oxygen use on coke rate and
iron runner temperatures (Table 21.4).
33
The main features when using oxygen are as follows
(valid for cold blast and hot blast cupolas)
• Reduction of blast air volume
• Reduction of coke rate
• Increase of metal temperature
• Increase of melt rate
• Reduction of top gas volumes
• Reduction of emissions of dust, CO, CO
2
and
SO
2
General oxygen enrichment in blast air is done with a
diffuser (Figure 21.14). There an oxygen pipe is installed
in the wind main to add oxygen to the blast air. The oxy-
gen mixes with the air and enters ...